SOLUTION: Find domain of: ln(9-8x-x^2) a = b = I know this requires some log rules I am just lost on solving please help!

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Question 914142: Find domain of: ln(9-8x-x^2)
a =
b =
I know this requires some log rules I am just lost on solving please help!

Found 2 solutions by ewatrrr, Fombitz:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
ln(9-8x-x^2) = ln((x-9)(x+1))
Keep in mind the Parent Function ln(x)
'x' must be > 0 ..so (x-9)(x+1) as well needs to be > 0
recommend a good graphing calculator/software to familiarize Yourself with the various Parent Functions
FREE graph software https://www.padowan.dk/download/

...........
ln((x-9)(x+1)) domain (−∞, -1) U ( 9, ∞)


Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
The only rule is that the argument be greater than zero.
9-8x-x%5E2%3E0
Graphing the function,
graph%28300%2C300%2C-10%2C2%2C-6%2C6%2C9-8x-x%5E2%29
The argument is positive between the values of -9 and 1 so the domain is,
(-9,1)
Here's a graph of the function.
graph%28300%2C300%2C-10%2C2%2C-6%2C6%2Cln%289-8x-x%5E2%29%29